Buenaventura’s 16-year San Gabriel mine boost: design and geomechanics lens
Reviewed by Tom Sullivan

First reported on MINING.com
30 Second Briefing
Buenaventura is weighing a 16‑year life extension for its San Gabriel underground gold mine in Peru’s Moquegua region, where current reserves exceed 1.8 million ounces and total measured, indicated and inferred resources top 2.4 million ounces. The operation, which poured its first gold bar in December 2025, is ramping from 2,000 tonnes per day by end‑2026 to a nominal 3,000 tpd in 2027, targeting more than 100,000 ounces of annual output. Around 90% of the rock mass is classed as low‑quality geomechanically, prompting adoption of a novel underground mining method in South America to improve selectivity and reduce dilution.
Technical Brief
- About 90% of the San Gabriel rock mass is classified as low geomechanical quality, driving method selection.
- Buenaventura reports using an underground mining method not previously applied anywhere in South America.
- The novel method is specifically aimed at improving orebody selectivity and limiting dilution in weak ground.
- Enhanced selectivity is also being used as a control on exposure time and worker safety in poor rock.
- Deposit geometry remains open both at depth and near surface, justifying continued brownfield drilling campaigns.
- New exploration results reported via Rumbo Minero underpin the potential 16‑year mine‑life extension.
- San Gabriel has been elevated to Buenaventura’s flagship development asset within its national mine portfolio.
- Brownfield life‑extension at San Gabriel reflects a regional shift, with Latin American gold producers favouring existing hubs over greenfield builds to manage capex.
Our Take
With 1.8Moz of gold reserves and 2.4Moz in total resources at San Gabriel, Buenaventura is positioning one of Peru’s larger undeveloped gold assets in our database, which could help offset investor focus on copper-heavy projects in the country.
The potential 16-year mine life extension at San Gabriel in southern Peru contrasts with recent permitting volatility seen at Peru’s $1.8 billion Tía María copper project, signalling that long-life gold projects in Moquegua may currently face a different risk–reward profile than large coastal copper builds.
The note that about 90% of San Gabriel’s rock mass is low-grade geomechanically implies a heavy reliance on ground support and sequencing to keep costs in check, a theme that recurs in several Latin American underground gold projects in our coverage where geomechanics, not grade, is the primary design constraint.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
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